package org.mybatis.generator.plugin;

import org.mybatis.generator.api.CommentGenerator;
import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.PluginAdapter;
import org.mybatis.generator.api.dom.java.*;
import org.mybatis.generator.api.dom.xml.Attribute;
import org.mybatis.generator.api.dom.xml.TextElement;
import org.mybatis.generator.api.dom.xml.XmlElement;

import java.util.List;

/**
 * <pre>
 * add pagination using mysql limit. 
 * This class is only used in ibator code generator.
 * </pre>
 */
public class PaginationMySQLPlugin extends PluginAdapter {
	@Override
	public boolean modelExampleClassGenerated(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {
		// add field, getter, setter for limit clause
		addLimit(topLevelClass, introspectedTable, "limitStart");
		addLimit(topLevelClass, introspectedTable, "limitEnd");
		return super.modelExampleClassGenerated(topLevelClass, introspectedTable);
	}

	@Override
	public boolean sqlMapSelectByExampleWithoutBLOBsElementGenerated(XmlElement element, IntrospectedTable introspectedTable) {
		// XmlElement isParameterPresenteElemen = (XmlElement) element
		// .getElements().get(element.getElements().size() - 1);
		//		XmlElement isNotNullElement = new XmlElement("isGreaterEqual"); //$NON-NLS-1$  
		//		isNotNullElement.addAttribute(new Attribute("property", "limitStart")); //$NON-NLS-1$ //$NON-NLS-2$  
		//		isNotNullElement.addAttribute(new Attribute("compareValue", "0")); //$NON-NLS-1$ //$NON-NLS-2$  

		XmlElement isNotNullElement = new XmlElement("if");
		isNotNullElement.addAttribute(new Attribute("test", "limitStart >= 0"));
		isNotNullElement.addElement(new TextElement(" limit #{limitStart} , #{limitEnd} "));
		// isParameterPresenteElemen.addElement(isNotNullElement);
		element.addElement(isNotNullElement);
		return super.sqlMapUpdateByExampleWithoutBLOBsElementGenerated(element, introspectedTable);
	}

	private void addLimit(TopLevelClass topLevelClass, IntrospectedTable introspectedTable, String name) {
		CommentGenerator commentGenerator = context.getCommentGenerator();
		Field field = new Field();
		field.setVisibility(JavaVisibility.PROTECTED);
		field.setType(FullyQualifiedJavaType.getIntInstance());
		field.setName(name);
		field.setInitializationString("-1");
		commentGenerator.addFieldComment(field, introspectedTable);
		topLevelClass.addField(field);
		char c = name.charAt(0);
		String camel = Character.toUpperCase(c) + name.substring(1);
		Method method = new Method();
		method.setVisibility(JavaVisibility.PUBLIC);
		method.setName("set" + camel);
		method.addParameter(new Parameter(FullyQualifiedJavaType.getIntInstance(), name));
		method.addBodyLine("this." + name + "=" + name + ";");
		commentGenerator.addGeneralMethodComment(method, introspectedTable);
		topLevelClass.addMethod(method);
		method = new Method();
		method.setVisibility(JavaVisibility.PUBLIC);
		method.setReturnType(FullyQualifiedJavaType.getIntInstance());
		method.setName("get" + camel);
		method.addBodyLine("return " + name + ";");
		commentGenerator.addGeneralMethodComment(method, introspectedTable);
		topLevelClass.addMethod(method);
	}

	/**
	 * This plugin is always valid - no properties are required
	 */
	public boolean validate(List<String> warnings) {
		return true;
	}

	// public static void generate() {
	// String config = PaginationPGPlugin.class.getClassLoader()
	// .getResource("mybatis-generator-config.xml").getFile();
	// String[] arg = { "-configfile", config, "-overwrite" };
	// ShellRunner.main(arg);
	// }
	//
	// public static void main(String[] args) {
	// generate();
	// }
}
